Cargo ships have been used for hundreds of years for the transportation of break bulk goods such as cocoa beans, coffee, sugar and rice. Typically, the goods are shipped from a country where the goods are grown where manual labor may be plentiful and relatively inexpensive to a more industrialized country where the goods are processed and/or consumed and where labor costs become a significant expense.
In the shipping industry, profit is made by keeping the ships on the move without significant delays in docking time for loading and unloading of goods which are being transported. When a ship comes to port, depending on the harbor, pilot tugs or the like may be employed to bring the ship to dock. Once docked, it is relatively impractical and inefficient to move the ship until it is ready to depart for its next destination.
Conventional ships have on-board crane systems to assist in the loading and unloading of cargo. Due to the limited reach of such crane systems, after a ship is docked, there is a relatively fixed embarkation/debarkation area on the dock defined by the reach of the ship's crane.
The shipping of break bulk goods such as cocoa beans from third world nations to the United States provides an example of the conventional shipping process. The cocoa beans are grown abroad, harvested and packed into 150 pound sacks. The sacks are transported to the dock area where they are placed on pallets having lifting slings attached, commonly referred to as a sling and/or sling load of cocoa beans. A typical sling of cocoa beans contains 30-35 sacks.
The slings of cocoa beans are arranged in groups adjacent to each other, the number of slings per group preferably equalling the capacity of the on-board crane which the ship employs. In view of the low labor cost in third world countries, it is not unusual to have the entire preparation operation done by manual labor. Accordingly, when the empty ship docks to pick up a load of cocoa beans, appropriate groups of slings of cocoa beans are in place on the dock to be loaded onto the ship by the ship's crane.
Typically, for a ship with a large capacity crane, only one or two groups of slings can be positioned on the dock in the embarkation area for the ship. As the ship's crane lifts the first group of slings and transfers the group into the ship's cargo hold, more slings of cocoa beans are assembled in the space vacated by the first group. The loading process continues until a desired number of sling groups are aboard the ship. As the groups of slings are placed in the hold of the ship, the groupings of slings remain intact to facilitate off-loading without any unnecessary handling.
Once loaded, the ship departs and sails to its destination such as a port in the U.S. When the ship docks, crews of stevedores stand ready to assist in the off-loading of the cocoa beans. The off-loading commences with the ship's crane being utilized to transfer the groups of slings of cocoa beans-from the ship's hold to the dock within the debarkation area defined by the reach of the ship's crane. Once the first group of slings of cocoa beans are in the debarkation area, they must be moved before subsequent sling groups of cocoa beans can be unloaded from the ship's hold.
Conventionally, stevedores employ forklifts to remove the slings from the debarkation area of the dock to a storage area, such as a warehouse. As soon as the slings are released from the crane, forklift operations commence. This method of ship unloading has been employed for many years and has been a reasonably satisfactory method of unloading break bulk goods such as cocoa beans from a ship.
Over the years, the capacity of ship cranes has gradually increased. At one time ship crane capacity was on the order of the 6-8 slings. That capacity has increased with newer cranes having the capacity of 10, 12 or 14 sling loads. Currently, the fourteen sling capacity crane is the largest crane used in commercial shipping of cocoa beans.
Applicant recognized that an alternative to the conventional off-loading method was needed to take better advantage of the larger capacity cranes now in use in commercial shipping. Applicant further recognized that the conventional dock handling procedures were in fact problematic, limiting to off-loading time and unnecessarily labor/cost intensive. For example, where a six sling capacity crane was used in off-loading, stevedores using forklifts could relatively easily remove the cocoa beans slings from the debarkation area without impeding the efficient utilization of the ship's crane. However, additional stevedore crew and forklifts were required to remove fourteen sling loads of cocoa beans from the debarkation area to the storage area to keep pace with the unloading of cocoa beans fourteen slings at a time with a fourteen sling capacity crane. Even with the addition of more stevedore crews and additional forklifts, at additional labor intensive cost, the congestion of forklifts and labor activity on the dock inherently limits the entire off-loading process to approximately 180-200 tons per hour. Accordingly, as set forth below, applicant has developed a new method of off-loading break bulk goods from ships in order to improve off-loading efficiency which has achieved off-loading rates as high as 380-400 tons per hour with lower labor costs.